What happened
On April 19, 2003, an AS350 B2 helicopter, registration I-AMVE, was performing ski-transport services (eliski) near Sestriere, Italy. The aircraft was transporting a second group of skiers to the Punta Ciatagnera area. During the flight, the engine suffered a sudden loss of power.
The pilot attempted to manage the emergency, with a surviving passenger reporting that the pilot shouted for everyone to jump. The helicopter struck a steep rocky slope at an altitude of approximately 2,850 meters. The impact caused the aircraft to break into two main sections. The crash resulted in 6 fatalities (the pilot and five passengers), while one passenger survived with serious injuries.
The investigation
The ANSV investigation focused on the mechanical condition of the Turbomeca Arriel 1D engine and the flight planning parameters. Investigators examined the engine components and found evidence of damage prior to the accident, specifically intergranular fractures and fatigue on turbine blades.
Technical analysis revealed that a required inspection, mandated by Alert Service Bulletin (ASB) n. A292-72-0263, had not been performed. This specific update was intended to monitor blade movement to prevent in-flight shutdowns. Furthermore, the investigation looked into the flight path and the aircraft's performance capabilities in the high-altitude, mountainous terrain.
Findings
- The primary cause of the accident was a sudden loss of engine power caused by the failure to implement the mandatory inspections outlined in ASB n. A292-72-0263.
- The aircraft was operating in a high-altitude environment where the combination of weight, temperature, and terrain placed the helicopter within an "avoidance zone," making an effective autorotation maneuver nearly impossible.
- Inadequate flight planning contributed to the severity of the event, as the chosen route did not provide suitable areas for an emergency landing.
- The operator lacked a required Route Manual, which should have established specific paths and safety protocols for single-engine operations in mountainous terrain.
- Discrepancies in weight and balance procedures were also noted as contributing factors.